This invention relates, in general, to portable security devices for preventing the unauthorized use of an electrically operated appliance or devices for receiving an electrical cord and attached plug.
Various devices have been proposed for preventing the unauthorized use of an electrical cord and attached plug. These devices can be categorized in five groups: key locked electrical switches, key locked electrical plugs, locking cover assemblies for electrical wall receptacles, and key locked electrical receptacles for appliance cord plugs and key locked devices for enclosing part or all of an appliance cord plug.
The electrical switch devices of the first group have the disadvantage of requiring initial fabrication as part of the appliance cord or severing of the appliance cord and subsequent installation. Such installation of the key lock switch generates increased labor costs and requires additional time compared with other devices that do not require connection directly to the appliance cord.
The devices of the second group possess the disadvantage of replacing the original plug with which the appliance was manufactured. The substitution of plugs creates increased costs, installation time, and inconvenience that would not otherwise be incurred.
The devices of the third group suffer the disadvantage of being associated with a particular stationary electrical wall receptacle and of thereby not being readily portable with one particular appliance. In addition, these inventions cannot be relied on, or carried with, a particular electrical appliance's plug or cord when the appliance is not being used. Therefore, such security devices, if designed to be otherwise separately portable, are very susceptible to loss or misplacement during transport of the particular electrical appliance.
The apparatus of the fourth group have the disadvantage of being cumbersome, somewhat complex, and relatively more costly as they include an electrical receptacle within a security container. Further, these devices are not as conveniently portable as may be desired owing to their typically larger mass and bulk.
The devices disclosed by the patents of the fifth group all have the disadvantage of lacking the capability to be retained on the cord or plug of the electrical appliance when the device is not being used to prevent the unauthorized use of the appliance. Therefore, such devices can be more easily lost or misplaced when the appliance is in use and the device is not performing its designated function.
Until the present invention, the various disadvantages associated with the above-discussed types of security devices tended to make the use of such devices less convenient than desired and tended to inhibit the wide spread use of such devices.
There is a need for an improved security device that would not have to be electrically connected to the cord or plug of the appliance. Elimination of such an installation requirement would reduce the time necessary to use the device and eliminate inconvenience associated with such installations in general.
It would also be desirable with such an improved portable security container to provide a means for attaching the container to the cord or plug of the electrical appliance, to ensure against the loss or misplacement of the container during use or non-use of the appliance.
Applicant is aware of the following U.S. Pat. Nos.:
4,407,554 to Drall which shows an electrical plug safety device.
4,413,488 to Harmison, Jr. which shows an electrical appliance lock.
4,445,738 to Wiencke which shows a locking device for electrical plugs.
4,488,764 to Pfenning et al. which shows a portable security container for an electrical cord and attached plug.
4,640,107 to Slade which shows a safety lock apparatus for an electrical plug.
4,647,735 to Sicher for an electrical security device.
4,653,824 to Jason et al. which shows a lock-out device for electrical appliances.
4,673,230 to Baumgart which shows a security device for electrical plugs.
4,674,813 to Feldner for an electrical lock.
4,705,335 to Goebel which shows a plug safe.
4,721,475 to Burke, Jr. which shows a safety shroud for an electrical connector.
4,782,971 to Hill which shows a device for preventing the unauthorized use of an electrical apparatus.
4,812,131 to Sieverman which shows an electrical plug lock apparatus.
4,846,708 to Marson et al. which shows a jack security device.
4,853,960 to Smith which shows a station interface and protector apparatus.
4,865,557 to Kershaw which shows a security device for electric appliances.
4,957,445 to Burke, Jr. which shows a lock-out enclosure for power connectors.
5,055,057 to Boyer which shows an electric plug lock.
5,061,194 to Herman et al. which shows an electrical connector lockout device.